China's best-known dissident today won the prestigious Nobel peace prize from the prison cell where he is serving 11 years for incitement to subvert state power.

The Norwegian Nobel committee praised Liu Xiaobo for his "long and non-violent struggle for fundamental human rights in China. The ... committee has long believed that there is a close connection between human rights and peace."

As the news was announced, transmission of both BBC news and CNN television channels was interrupted in China.

The decision will infuriate the Chinese government. A foreign ministry spokeswoman said last week that awarding Liu the prize would contradict the aims of the award. The director of Norway's Nobel institute said a senior Chinese official had warned that Sino-Norwegian relations would be damaged if Liu won.

Today, committee chairman Thorbjoern Jagland said China should expect to be put under greater scrutiny as it becomes more powerful: "We have to speak when others cannot speak. As China is rising, we should have the right to criticise ... We want to advance those forces that want China to become more democratic."

Czech playwright and former president Václav Havel and Nobel peace laureate Desmond Tutu were among those who had supported Liu for his "unflinching and peaceful advocacy for reform".

Liu was first jailed for his role in the Tiananmen Square student reform movement. He also served three years in a labour camp in the 90s.

"There was never a question for him of abandoning the struggle, although he was very critical about the [1989 student] movement," said Jean-Philippe Béja, of the Paris-based Centre for International Studies and Research, who first met Liu in the early 90s.

"He is a person who wants to live in truth."

It is highly unlikely that the 54-year-old author and former academic knows he has won. His lawyer told him his name had been put forward, but it is thought he knows little about the nomination because he is not permitted to talk about current affairs with visitors to his prison in Jinzhou, Liaoning province. He is allowed to see his relatives for an hour each month. His wife, Liu Xia, had said she believed he was unlikely to win the prize, but that she thought the attention he gained had won him better conditions in prison.

Several Chinese dissidents took the bold step of signing a letter supporting his nomination.

In an article backing him for the prize, the philosopher Xu Youyu wrote: "His activities in 1989 can be seen as formative in the entirety of his following writings and other works, characterised by an unwavering bravery and refusal to back down in the face of danger and suppression, by the pursuit and defence of human rights, humanism, peace and other universal values and, finally, adherence to the practice of rational dialogue, compromise and non-violence."